How to use Rust to create a Netlify Serverless function

Enabling the feature

While support is still experimental, support for rust server less functions must be enabled on a per-site basis. You can enable rust support by enabling this environment variable

netlify env:set NETLIFY_EXPERIMENTAL_BUILD_RUST_SOURCE true

Creating a serverless function

In order to create a new rust function use cargo to initialize a new project

cargo init FUNCTION_NAME

The name you choose for the function determines its endpoint. For example, running cargo init hello will create a function which, when deployed, will be accessible on the /.netlify/functions/hello endpoint.

Alternatively, you can get a jump-start with the Netlify CLI’s function generator. Run netlify functions:create —language=rust, choose a template, and you’ll get a fully working function, ready to be deployed and modified to fit your needs.

Structure

use aws_lambda_events::event::apigw::{ApiGatewayProxyRequest, ApiGatewayProxyResponse};
use aws_lambda_events::encodings::Body;
use http::header::HeaderMap;
use lambda_runtime::{handler_fn, Context, Error};
use log::LevelFilter;
use simple_logger::SimpleLogger;

#[tokio::main]
async fn main() -> Result<(), Error> {
    SimpleLogger::new().with_level(LevelFilter::Info).init().unwrap();

    let func = handler_fn(my_handler);
    lambda_runtime::run(func).await?;
    Ok(())
}

pub(crate) async fn my_handler(event: ApiGatewayProxyRequest, _ctx: Context) -> Result<ApiGatewayProxyResponse, Error> {
    let path = event.path.unwrap();

    let resp = ApiGatewayProxyResponse {
        status_code: 200,
        headers: HeaderMap::new(),
        multi_value_headers: HeaderMap::new(),
        body: Some(Body::Text("Hello world".to_owned())),
        is_base64_encoded: Some(false),
    };

    Ok(resp)
}

How to use Rust to create a Netlify Serverless function

Enabling the feature

Creating a serverless function

Structure

Links

YouTube